Browse free open source Email software and projects for Windows below. Use the toggles on the left to filter open source Email software by OS, license, language, programming language, and project status.
An easy-to-use anti-spam email gateway
Anti-Spam SMTP Proxy Server implements multiple spam filters
Windows eml and mbox viewer.
The classic email sending library for PHP
SMTP email proxy and relay server
Sync Outlook with Google, SOGo or any other CalDAV / CardDAV server
Unified Communications Server
An automated e-mail OSINT tool
Powerful Open Source Email Marketing app with analytics & segmentation
A faster, leaner email client and fork of Nylas Mail
Sync Outlook contacts and calendars with Google
E-mails, subdomains and names
Phishing Campaign Toolkit
Simple, web-based address & phone book
A program to send mail via SMTP from command line
Take back control of your email with this mail server in a box
SendMail is a simple program that can send e-mails via SMTP protocol.